Prefilled syringes of this type are known; they are usually manufactured with a syringe cylinder of glass, wherein on that side of the syringe cylinder distant to the syringe plunger there is provided a syringe connection which is sealingly closed by way of a further component.
With the state of the art known from U.S. Pat. No. 5,989,227, this further component is a sealing element which is rigidly connected to and is to remain on the syringe connection. For removing the fluid located in the syringe cylinder this closure must be pierced by way of a cannula. The solution known from U.S. Pat. No. 5,135,496 is more favorable inasmuch as this further component already has a though-bore which at the end is sealed by way of a closure plug which must first be directly removed before use. The embodiment form described here however is extremely complicated in its construction since apart from the syringe cylinder three or four further components are required.
U.S. Pat. No. 5,833,653 discloses a syringe connection which is closed by way of a further component which although comprising a central though-bore, is however closed by way of a membrane. In order to release this connection the syringe cylinder is pressed in, by which means the membrane is deflected outwards due to the increased inner pressure, and here is pierced by a spike-like plug which projects into the Luer connection of the syringe. Disregarding the fact that this solution is also complicated in its design due to the multitude of components, the design of the membrane is very difficult with regard to manufacturing technology and is thus expensive. Specifically it needs to be thin enough such that with the impingement of pressure it bulges sufficiently towards the spike, and on the other hand it must be thick enough to reliably close off the contents.
For syringes with a syringe cylinder consisting of plastic, a similar closure variant is known from U.S. Pat. No. 5,624,402. The closure element to be placed onto the syringe connection likewise consists of a multitude of components and requires a costly manufacture and is thus expensive.